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A new method, passive flux meter (PFM), has been developed and field-tested for simultaneously measuring contaminant and groundwater fluxes in the saturated zone at hazardous waste sites. The PFM approach uses a sorptive permeable medium placed in either a borehole or monitoring well to intercept contaminated groundwater and release "resident" tracers. The sorbent pack is placed in a groundwater flow field for a specified exposure time and then recovered for extraction and analysis. By quantifying the mass fraction of resident tracers lost and the mass of contaminant sorbed, groundwater and contaminant fluxes are calculated. Here, we assessed the performance of PFMs at the Canadian Forces Base Borden field site in Ontario, Canada. Two field tests were conducted under imposed groundwater flow fields: (1) radial flow to a well and (2) linear flow in a test channel confined by sheet pile walls on three sides. Both tests demonstrate that the local fluxes measured by PFM and averaged overthe screen interval were within 15% of imposed groundwaterflow and within 30% of measured contaminant mass flux. Patterns in depth variations in groundwater and contaminant fluxes, determined by the PFM approach, allow for site characterization at a higher spatial resolution. These results support the PMF method as a potential innovative alternative for measuring groundwater and contaminant fluxes in screened wells.

The results of brain connectivity analysis using reconstructed source time courses derived from EEG and MEG data depend on a number of algorithmic choices. While previous studies have investigated the influence of the choice of source estimation method or connectivity measure, the effects of the head modeling errors or simplifications have not been studied sufficiently. In the present simulation study, we investigated the influence of particular properties of the head model on the reconstructed source time courses as well as on source connectivity analysis in EEG and MEG. Therefore, we constructed a realistic head model and applied the finite element method to solve the EEG and MEG forward problems. We considered the distinction between white and gray matter, the distinction between compact and spongy bone, the inclusion of a cerebrospinal fluid (CSF) compartment, and the reduction to a simple 3-layer model comprising only the skin, skull, and brain. Source time courses were reconstructed using a beamforming approach and the source connectivity was estimated by the imaginary coherence (ICoh) and the generalized partial directed coherence (GPDC). Our results show that in both EEG and MEG, neglecting the white and gray matter distinction or the CSF causes considerable errors in reconstructed source time courses and connectivity analysis, while the distinction between spongy and compact bone is just of minor relevance, provided that an adequate skull conductivity value is used. Large inverse and connectivity errors are found in the same regions that show large topography errors in the forward solution. Moreover, we demonstrate that the very conservative ICoh is relatively safe from the crosstalk effects caused by imperfect head models, as opposed to the GPDC.

Flame retardant epoxy is closely related to the safety of a human's life against the surrounding fire threat. Flame retardant properties can be obtained by supplementing with additives, such as phosphorus compounds and nanomaterials, or synthesizing flame retardant monomers. The principle of improving flame retardancy is based on the capture of oxygen radicals and the formation of a char layer, which blocks flammable gases. This paper focuses on a flame retardant epoxy resin using naturally occurring tannic acid (TA) as a hardener, which is both an oxygen-radical quencher and a charring agent. TA is reacted with the commercially available diglycidyl ether of bisphenol A (DGEBA). The reaction between the epoxy ring of the DGEBA and multiple functional groups in TA is empirically demonstrated using dynamic scanning calorimetry (DSC) and Brillouin spectra. The most effective flameretardant TA-DGEBA (TD) thermoset had an limiting oxygen index (LOI) value 46% higher than the control sample. This result suggests that TA-based epoxy resins could be promising flame-retardant polymers.

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High signal on T1 -weighted image and numerous signal voids are highly suggestive of ASPS, although they are not universal as has been suggested and arteriovenous malformation should be included in the differential diagnosis. Local bony metastases in ASPS were seen in two cases and should be carefully investigated.

Ionic polymer-metal composites (IPMCs) have been proposed as biomimetic actuators that are operable at low applied voltages. However, the bending strain and generating force of the IPMC actuators have generally exhibited a trade-off relationship, whereas simultaneous enhancement of both the qualities is required for their practical applications. Herein, a significant improvement in both the strain and force of the IPMC actuators is achieved by a facile approach, exploiting thickness-controlled ion-exchange membranes and nanodispersed metal electrodes. To guarantee a large generating force of the IPMC actuators, ultrathick ion-exchange membranes are prepared by stacking pre-extruded Nafion films. Metal electrodes with a nanodispersed structure are formed on the membranes via alcohol-assisted electroless plating, which allows increased capacitance and facilitated ion transport. The resulting actuators exhibit greatly enhanced electromechanical properties, including an approximately four times larger strain and two times larger force compared to those of actuators having the conventional structure. Moreover, the ability to lift 16 coins (a weight of 124 g) has been successfully demonstrated using ultrathick IPMC actuators, which shows great promise in realizing artificial muscles.